Jeff,
I would just do a fresh oil change with the recommended amount of oil and run it for a few minutes to fill everything up then let it settle for 10 minutes, I do not have a 235 but would think it would be 5 qrt.
Then just set your "NEW" unmarked stick in an use that level as your FULL mark.
The 235 is 5 quarts without filter, 6 quarts with filter.
